Rotatable-grate furnace.



UNITED sTATEs PATENT oEEIoE.

ADAM HEINRICH LUDWIG HALLAscHKAv ANDfKARL ALFRED GRIMM, oF cAssEL, GERMANY. A

` RorATABLE-GRATE FURNAGEQI Apprenti@ med February 28,1906. serial 110.303.561.

ence being had therein to the accompanying drawings.

' 'My invention 'relates to -a rotatable-grate furnace which may be employed in stoves of every description, beneath steam-boilers, and for all other purposes, and presents the advantage that by actuating the rotatablegrate furnace from without the fuel can be Well poked and freed from. the ashes and slags. Also by consecutively exposing other parts of the rotatable-grate furnace to the action of the fire the life of the grate can be lengthened. According to its size the rotatable-grate furnace may consist of one or several parallel rollers, which are preferabl grooved and perforated,'also serrate on botii sides, and are arranged to be turned from without. The one or severalrollers are disposed within .a frame, near the front partion of which a detachable grate-bar is disposed, so that by lifting the lattera large opening ma be lformed through which the ashes and s ags or all the fuel can be better discharged. Y

We will now proceed to describe our inven- 'tion with yreference tothe .accompanying drawings, in which- Figure 1 is a vertical longitudinal section through the lower part of a German stove and a rotatable-grate furnace disposed thereir 1.` `Fig. 2 is a vertical cross-section through 1 the same. Fig.` 3 is a horizontal sectional view of a form having a hollow roller. Fig. 1 is a horizontal section through the s'ame on the line C D in Fig. 2. Fig. 5 shows part of a grooved and perforated roller, partly in Aelevation and partly in section. Fig. 6 is on the left a cross-section through the same and on the right an end view of the same. Fig. 7 is a longitudinal section through a rotatablegrate furnace beneath a steam-boiler, and ig. 8 is a horizontal section through the same on the line E Fin Fig. 7.

Similar letters of' reference refer to similar v parts -throughout the several views.

Specification of Letters 'Patent v'by means of any known device s.

Patented Nov. 6,1906.

A rotatable-grate furnace of the smallest size and simplest construction is shown at Figs. 1 to 4, which represent a German stove. We do not further describe the construction of the latter, as it is immaterial. A frame b of convenient shape is disposed in the firespace of the stove close to the walls of the latter, also two plates or sup orts c c are disiposed, in which the shaft d of) a smooth roller a is mounted to turn. The roller a is solid and is provided with several lon itudinal ,channels r 1', which are inclined wit regardl `to the shaft d or may be laced spirally.. To

pevent the ashes and s ags or' arts of the e from blocking up the space etween the roller a and the frame b, the top surface of the latter is preferably placed'above the axis Jof the roller a intermediate of its radius. lThe rear portion 4of the frame b is preferably bevy eled off at f, so as to permitl the ashes andslags to slide off through thes ace between this frame ortion and the rol er a'into the ash-pit. frame b a detachable vslotted grate-bar m is disposed, which is' preferably provided with two pins or projections n 'n for enga 'ng'in corresponding recesses in the two si e portions of the frame b, Thereby the grate-bar m is prevented from shifting in the cross direction. It is provided with a knob o or the like by means of which it can be seized and lifted. A hand-crank g is fastened at the external end of the shaft d and can be locked This rotatable-gratefurnace is o erated las follows:

VThe combustible is intro uced into the firechamber from labove or through the' dooropening p, as the .case may be, and the fire is kindled as usual. When during the combustion of the fuel ashes and slags are formed or C ose to the front portion of the both directions, as the circumstances may render it necessary, so that the fuel is stirred and mixed, also freed from the ashes and slags, whichdrop through the spaces betweeln and the detachab e the roller a, the frame grate-bar m. Airis constantly supplied to the fire from the ash-pit through the inclined or spiral channels r r in the roller a, also through the slot of the grate-bar m and through the spaces between the roller a, theframe b, and the grate-bar m.` It will be seen that the supply of airvcannot be stopped, as the inclined or spiral channels r 1" are not likely to be blocked up by reason of their inclination and all the ashes and slags can be discharged by merely turning the handcrank g. The device s may be employed for locking the hand-crank to prevent' the roller a from inadvertently moving. For discharging a large quantity of ashes and slags or the whole fuel under circumstances it may be preferable to seize the detachable grate-bar m at its knob 0 and to remove it, so that a large opening will be left between the roller a and the front portion of the frame l), through which opening the mass can drop into the ash-pit.

For larger grate-surfaces it is preferable to make the roller a hollow and to provide it with spiral grooves h on its outside, also with spiral grooves C on its inside; further, with a plurality of conveniently-disposed air-openings i i, and at last with preferably radial teeth. t on the end faces along the peripheries, as is clearly shown at Figs. 5 and 6. The spiral surfaces of the roller serve to break up any slag and shift it lengthwise ofthe roller as the latter turns. Further, the teeth t at the sides will equally break up any slags in the spaces between them and the side portion of the yframe b and force them downward. At last all ashes and slags which may have dropped through the upper openings i into the cavity of the roller a, and cannot at once escape through the lower openings 'iv will be conducted longitudinally through the internal, spiral grooves le until they drop either through air-openings i or at the side of the roller a. I

Figs. 7 and 8 show a larger rotatable-grate furnace beneath a steam-boiler and provided with three grooved and perforated rollers a a of the' construction shown at Figs. 5 and 6 and described above. These three rollers may be geared with each other in any known manner-for example, by means of the three gear-wheels g g, (shown at Fig. 8,) so that they ,can be simultaneously turned. The frame b is modified in its shape in accordance with its size, and its projecting rear portion is provided with an inclined surface f, the same as before. The detachable grate bar m is shown without any longitudinal slot; but this is immaterial. The two pins or projections n n of this detachable grate-bar m also engage in corresponding recesses in the two side portions of the frame b to prevent the gratebar from shifting in the cross direction. A single hand-crank g is provided for simultaneously turning the three rollers a a by means ofthe three gear-wheels g g. The operation of this large rotatable-grate furnace is substantially the same as before. By turning all the three rollers a, a with the aid of the hand-crank g the fire can be thoroughly poked and an easy manner.

Also the advantage -is. obtained that the three rollers a, a are prevented from wasting too rapidly, as they can be turned to present other portions to the action of the lire. A locking device of any known construction may be provided to prevent the three rollers a a from inadvertently turning during the charge of the furnace. l

The rotatable-grate furnace may be varied in many respects without deviating fromthe spirit of our invention.

What we claim as our invention, and desire to secure by Letters Patent, is-

l. The combination with a stove or furnace of a frame located therein including a rear iixed bar and a front substantiallyhorizontally-disposed bodily-removable bar supportedv at its opposite end edges, a roller j ournaled beneath the bars having a portion of its periphery projecting thereabove and located in close juxtaposition thereto, and means for rotating the roller, substantially as described.

2. In a furnace, .the combination with a frame surrounded by the furnace-walls and having an inclined upper surface on its projecting rear portion, of a horizontal hollow roller with serrate ends and being spirally grooved and perforated and leaving narrow spaces along the rear and the two side portions respectively of said frame, two pins on said horizontal hollow roller in its axis and mounted in said frame to turn, a detachable grate-bar adjacent to the front portion of said frame and leaving a narrow space along said horizontal hollow roller and engaging in recesses in the two side portions of said frame, and means for turning the one of said two pins and thereby said horizontal hollow roller from without, said horizontal hollow roller projecting a little above the u per surfaces of said frame and the incline surface of the projecting rear portion of the latter sloping downward toward it.

3. In a furnace7 the combination with a frame surrounded by the furnace-walls and having an inclined upper surface on its rojecting rear portion, of a horizontal ho low roller having serrated sides and an internally and externally grooved cylindrical wall7 said wall and the end wall of the roller being provided with perforations, said roller being located in the frame to leave narrow spaces along the rear and two side portions respectively of said frame, two pins on said horizontal hollow roller in its axis and mounted in said frame to turn, a detachable grate-bar adjacent to the front portion of said frame and leaving a narrow s ace along said horizontal hollow roller and) engaging in recesses in the two side portions of said frame, and means for turning the one of said two pins and thereby said horizontal hollow roller from without, said horizontal hollow roller projecting a little above the upper surfaces IOO IIO

. of said frame and the inclined surface' of the projecting rear portion of the latter sloping downward toward it.

1l.A Ina furnace, the combination with a frame surrounded by the furnace-walls and having an inclined upper surface on its projecting rear portion, of a plurality of horizontal hollow rollers with serrate ends and placed. parallel and adjacent to each other and mounted in said frame to turn, they being sp'irally grooved and perforated and leaving narrow spaces along the rear and the two si e portions respectively of said frame, a detachable grate-bar ad`acent to the front portion of'said frame an leaving a narrow space along the front one of said plurality of horizontal hollow rollers and engaging in recesses in the two side portions of said frame, and means' for turnin said plurality of horizontal hollow rollers rom without, said horizontal hollow rollers iprojecting alittle above the upper surfaces o said frame and the inclined surface of the projecting rear ortion of the latter sloping downward towar them.

5. In a furnace, the combination with a frame surrounded by the furnace-walls and l having an inclined upper surface on its projecting rear portion, of a plurality of horizontal hollow rollers with serrate ends and placed parallel and adjacent to each other and mounted in said frame to turn, they be-v ing spirally grooved externally and internally and perforated in the mantle and in the sides and leaving narrow spaces along the rear and the two s1de portions respectively of said frame, a detachable grate-bar adjacent to the front portion of said frame and leaving a narrow space along the front one of said plurality of horizontal hollow rollers and engaging in recesses in the two side portions of said frame, and means for turning said plurality of horizontal hollow rollers from without, said horizontal hollow rollers rojecting a little above the u per surfaces o'IPsaId frame and the incline surface of the projecting rear portion of the latter sloping downward toward them. In testimony whereof we have affixed our signatures in presence of two witnesses. f

Witnesses: n

PAUL SCHMIDT, VERNEST RECH. 

